Press for cutting sheet material

ABSTRACT

A press for cutting sheet material includes a waste stripping section and is provided with waste ejecting elements supported by two frames which, in turn, are slideably receivable within two relatively moveable carriages whereby the frames can be slideably withdrawn from the carriages in order to permit adjustments of the stripping tools.

United States Patent n91 Bobst et al. 0

m1 3,786,731 [4 1 Jan. 22, 1974 PRESS FOR CUTTING SHEET MATERIAL [75] Inventors: Jacques Bobst, Epalinges; Walter Gruetter, Morrens; Edwin Bollinger, Morges, all of Switzerland [73] Assignee: J. Bobst & Fils, S.A., Prilly,

Switzerland 22 Filed: July 10, 1972 21 Appl. No.: 269,952

[30] Foreign Application Priority Data July 13, 1971 Switzerland 10303/71 [52] US. Cl. 93/36 A, 83/564, 83/700, 93/59 ES [51] Int. Cl B31!) 1/74 [58] Field of Search..... 93/36 A, 36 R, 59 ES, 58.5; 83/563, 564, 698, 699, 700

[56] References Cited UNITED STATES PATENTS 3,060,776 10/1962 Bobst et al 93/36 A X 3,167,992 2/1965 Kury 83/700 2,557,504 6/1951 Holmes 2,220,296 1 1/1940 Simister 3,055,275 9/1962 Schroter 3,249,272 5/1966 Scarpa 93/36 A X Primary Examiner-Roy Lake Assistant Examiner-James F. Coan Attorney, Agent, or Firm-Hill, Sherman, Meroni, Gross & Simpson [5 7] ABSTRACT A press for cutting sheet material includes a waste stripping section and is provided with waste ejecting elements supported by two frames which, in turn, are slideably receivable within two relatively moveable carriages whereby the frames can be slideably withdrawn from the carriages in order to permit adjustments of the stripping tools.

4 Claims, 6 Drawing Figures SHEET 1 BF 3 Fig.6'

Fig. 5

PATENTEDmezmm sumsnr's Fig. 3

PRESS FOR CUTTING SHEET MATERIAL BACKGROUND OF THE INVENTION The present invention pertains to a press for cutting sheet material such as paper, cardboard, corrugated cardboard, and the like, and is particularly directed to a press which includes a stripping station wherein previously cut portions of a sheet of material are stripped" from the remainder of the sheet to effect waste removal in a fast and efficient manner.

The stripping sections of such presses (particularly those which are used for working on corrugated cardboard stock) are commonly arranged with mating pairs of stripping tools carried in two relatively moveable frames which are positioned parallel to the path of movement of the sheet stock through the machine and which are moveable toward and away from such stock.

Each time a different job is being run on the ma- .chine and a new and different cutting design is installed at the cutting station it is necessary to re-adjust the positions of the respective stripping tools relative to the sheet itself and relative to one another.

Heretofore, it has generally been necessary to set the cutting die outside of the machine and take such measurements as are necessary to determine the precise locations at which the stripping elements should be located in order to effect a proper waste stripping action and then to use these measurements for determining the positioning of the stripping tools. Such functions have to be done by the operator while he leans into the stripping station of the machine by measuring the distance from the sides and ends of the stripping station to position the stripping tools and it is not generally possible to determine precisely the accurate positions for such stripping tools.

SUMMARY OF THE INVENTION In accordance with the present invention the upper and lower frames which carry the mating stripping tools are each carried in carriages which, in turn, are adapted to move vertically relative to the path of movement of sheet stock positioned therebetween.

When it is desired to set up a new job the frames carrying the stripping elements can be slideably removed from the carriages so as to extend outwardly from the side of the press. The operator is then free to position the new job design directly over the stripping elements without having to lean into the machine and can then precisely and accurately adjust the stripping elements relative to the waste portions in the sheet and relative to one another without having to do so by making careful measurements.

The frames carrying the stripping elements are then slid back into their respective carriages and means are provided for locking the frames within those carriages. When the press is again activated the carriages will move relative to one another with the frames being fixedly mounted therein and the stripping elements will then engage the waste portions and effect the stripping operation.

Accordingly it is an important object of this invention to provide a press for cutting strip material wherein the frames which carry the tools and which are designed for movement relative to a sheet to be stripped can be slideably withdrawn from the press so that adjustments 0f the tools can be effected with the supporting frames extending exteriorly of the press body.

Another and more specific object of the invention resides in the design of a press wherein two generally horizontally extending cradles carry two generally horizontally extending carriages which, in turn, carry horizontal frames which in turn carry stripping tools and wherein the frames are horizontally slideably mounted within the respective carriages and wherein the upper of the two mating carriages is pivotally mounted in its respective cradle.

These and other objects, features, and advantages of the present invention will be more fully understood from the following descriptions taken in conjunction with the drawings, although variations and modifications of the invention may be effected without departing from the spirit and scope of the novel concepts of the disclosures as specifically defined in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the stripping station of a press for cutting sheet material showing the frames carrying their respective stripping tools partially withdrawn from the side of the press;

FIG. 2 is a side elevational view of the relevant portions of the stripping station of such a press showing some parts in vertical section and others in side elevation;

FIG. 3 is an end view of the stripping station shown in FIG. 2 and also showing some parts in vertical section and others in side elevation;

FIG. 4 is a fragmentary plan view of the outer edge of the lower frame and its associated parts;

FIG. 5 is a fragmentary side elevation view of the frame locking mechanism; and

FIG. 6 is a fragmentary sectional view of the frame locking mechanism illustrated in FIG. 5.

A press for cutting sheet material generally includes a feed station, a cutting and creasing station, a stripping station, and a delivery station. Sheets of material to be worked are fed from the feed station to the cutting and creasing station wherein portions of the sheet stock are both cut and creased and the sheet material is then fed to the stripping station where the waste material which has been cut from the sheet stock in the previous station is removed and thereafter the cut and stripped sheet material is directed to the delivery station.

FIG. 1 illustrates only the stripping station of such a press and it should be understood that the view shows primarily the side of such a press and that as viewed in FIG. 1 the feed and cutting stations would be toward the right and the delivery station would be toward the left.

The portion of the press shown in FIG. 1 comprises a housing 1 having a board 20 mounted therein (as shown in broken lines) which board is designed to support the sheet material fed to the stripping station. Upper and lower frames 3 and 4 serve to support mating pairs of upper and lower stripping tools 5 and 6.

The board 20 is normally apertured so as to permit the lower stripping tools 6 to extend upwardly through the board and into engagement with such sheet material as is carried on the board. The upper and lower stripping tools move into engagement with a portion of the sheet to be stripped and sandwich such waste portion of the sheet between themselves and thereafter the stripping tools and the waste portion of the sheet are caused to move together relative to the plane of the sheet so as to positively effect the stripping operation.

The stripping tools, 5, 6 are caused to move periodically toward and away from the sheet material carried on the board 20 by reciprocation of the frames 3, 4 in a manner which will be more completely understood by reference to the remaining figures and the description given in connection therewith.

Referring initially to FIG. 3 the housing 1 has a horizontally disposed cradle 7 mounted for vertical reciprocable movement within the stripping station. Connecting links 10 and 11 serve to pivotally interconnect the opposite ends of the cradle 7 with arms 12 and 13 which in turn are pivotally mounted on the housing about the axes 14 and 15. Arms 12 and 13 may be formed integrally with drive arms 16 and 17 and these arms, in turn, are interconnected by the link 18 so as to rotate together and thereby cause the cradle 7 to move up and down. The member 13, 17 has still another arm 19 extending therefrom which arm is connected to a reciprocably moveable drive member which need not be described herein in detail but which effects the drive for the reciprocably moveable cradle 7.

A board 20 is mounted within the housing at the points 21 and is adapted to support a succession of sheets to be stripped. The board 20 may be apertured at suitable locations so as to permit the stripping tools supported by the lower cradle to extend up through the board and engage the sheet supported on the upper surface of the board. An upper cradle 22 is positioned above the board 20 in spaced relation therefrom and it too is carried by connecting links 23, 24 which are pivotably mounted on the distal ends of arms 25, 26

which, in turn, are pivotably mounted on the housing about axes 27, 28. Drive arms 29, 30 are formed integrally with arms 25 and 26 and are interconnected by a link 31. Arm 32 is also formed integrally with arms 26, 30 and is interconnected with the same drive mechanism connected to the arm 19 so that the cradles 7 and 22 are caused to remain in a horizontal position and move together reciprocably toward and away from the board 20.

In operation, a sheet which has already been cut but has not had the waste portions moved, is moved into position on the board 20. In a sheet fed press this is generally accomplished by means of gripper bars which extend transversely across the press and which are carried by chains 33, 34 which, in turn, are guided along chain guides 35, 36. Operation of the drive mechanism for the cradles 7, 22 causes these two elements to move toward the board 20 and the stripping tools 6, 5 supported respectively by those cradles move toward one another and into contact with the waste portion of the sheet mounted on the board 20. A mating pair of upper and lower stripping tools engage a waste portion of the sheet to be stripped and these tools and the sandwiched waste material are then caused to move slightly above the plane of the remainder of the sheet so as to positively effect the stripping operation.

In accordance with the present invention the upper stripping tools are not mounted directly on the cradle 22 but are mounted on a frame 38 which is in turn mounted for horizontal sliding movement in carriages 2211 which, in turn, is carried by the cradle 22. It is sometimes desirable or necessary to raise the upper frame in order, for instance, to remove jammed paper from the stripping station. For this reason means are provided to permit the entire carriage 22a along with the frame 38 to be pivotally moved within the stripping station. To accomplish this result the carriage 22a is in turn supported by the cradle 22 and has its lower surface 22b resting on a shoulder 22c of the cradle 22 as shown in FIG. 2.

The frame 37 is slidably mounted in a guideway 37a formed in the lower cradle 7 itself so that it too can be horizontally withdrawn from the side of the press. The frame 37 has a vertically extending plate 39 connected to its left hand end (as viewed in FIG. 3) and this plate has its right vertical surface maintained in engagement with an abutment 40 by means of a fastener 41. When the fastener 41 is released, the frame 37 can be withdrawn horizontally from the cradle 7 in the manner illustrated in FIG. 1.

In the same manner the frame 38 can be withdrawn horizontally from the carriage 22 upon release of a fastener 42 which maintains a plate 43 connected to the frame 38 in engagement with an abutment 44.

With this arrangement the stripping tools 5, 6 to be mounted on the frames 38, 37 can be accurately positioned with respect to one another and with respect to a sheet to be stripped while the two frames 38, 37 are Withdrawn from the side of the press.

A locking mechanism 45 is provided to positively lock the carriage 22a and the cradle 22 together for comovement. It consists of a pair of rods 46 which are guided for slideable movement within brackets 47 and are so designed that upon rotational movement of a lock arm 48, the rods 46 will each be caused to move outwardly and into corporate openings 49 formed in the cradle 22. Upon movement of the arm 48 to the right as seen in FIG. 2 the rods 46 are withdrawn from the openings 49 and the carriage 22a along with its frame 38 can be pivoted about its axes 50 in the manner shown in broken lines in FIG. 3. It will be noted that pivoting of the carriage 22a will nearly always be affected when the carriage is in its uppermost position.

It would appear from the foregoing description of the preferred embodiment of our invention that a practical and efi'icient'means of effecting stripping tools adjustably in a press has been provided and that although there may be variations and modifications made by those skilled in the art, it is our desire to include these variations and modifications within the scope of our invention as defined by the appended claims.

What we claim is:

1. In a press for carrying sheet material wherein waste is stripped from the sheet material by stripping tools, the improvement which comprises: a cradle mounted for reciprocable movement within said press relative to the sheet to be stripped, a carriage mounted for pivotable movement on said cradle, a frame mounted for slideable movement within said carriage whereby said frame can be withdrawn from the side of said carriage and press, and stripping tools mounted on said frame.

2. A press constructed in accordance with claim 1 wherein locking means are provided to lock said carriage in fixed position within said cradle and for locking said frame in fixed position within said carriage.

3. In a press for cutting sheet material wherein waste is stripped from the sheet material by mating pairs of stripping tools, the improvement which comprises: a

said upper and said lower frames, and means mounting the carriage within said upper cradle for pivotable movement on said cradle.

4. A press constructed in accordance with claim 3 wherein locking means are provided for positively locking said carriage for non-pivoting movement within said upper cradle and for locking each of said frames within said carriages. 

1. In a press for carrying sheet material wherein waste is stripped from the sheet material by stripping tools, the improvement which comprises: a cradle mounted for reciprocable movement within said press relative to the sheet to be stripped, a carriage mounted for pivotable movement on said cradle, a frame mounted for slideable movement within said carriage whereby said frame can be withdrawn from the side of said carriage and press, and stripping tools mounted on said frame.
 2. A press constructed in accordance with claim 1 wherein locking means are provided to lock said carriage in fixed position within said cradle and for locking said frame in fixed position within said carriage.
 3. In a press for cutting sheet material wherein waste is stripped from the sheet material by mating pairs of stripping tools, the improvement which comprises: a pair of generally horizontally extending cradles positioned on opposite sides of a sheet to be stripped, means mounting said cradles within said press for reciprocable movement relative to the sheet to be stripped, a carriage mounted within one of said cradles, a frame mounted for horizontal sliding movement within one of said cradles and said carriage, whereby said frame can be withdrawn from the side of said press, cooperating pairs of stripping tools mounted on said upper and said lower frames, and means mounting the carriage within said upper cradle for pivotable movement on said cradle.
 4. A press constructed in accordance with claim 3 wherein locking means are provided for positively locking said carriage for non-pivoting movement within said upper cradle and for locking each of said frames within said carriages. 